The present invention relates to exercise devices, and more particularly concerns exercise devices for wear with, or as part of, a shoe.
Many footwear exercising devices have been proposed in the prior art for exercising the leg and back muscles. Examples of such devices can be found in the following U.S. Pat. No. 2,769,252 by A. E. Monier; U.S. Pat. No. 3,472,508 by Baker et al.; U.S. Pat. No. 3,926,181 by Holcombe, Jr.; U.S. Pat. No. 4,573,678 by Lamb et al.; U.S. Pat. No. 4,681,114 by Lodispoto; and U.S. Pat. No. 4,934,073 by Robinson. While these devices may be suitable for a particular purpose to which they address, it will be apparent to those skilled in the art that said devices would not be as suitable for the purposes of the present invention. Indeed, the devices of Monier, Baker et al. and Lamb et al. are all designed for purely therapeutic purposes, making it very difficult to wear such exercise devices throughout the activity of a normal day. On the other hand, the devices of Holcombe, Jr., Lodispoto and Robinson are designed for more prolonged wear. However, neither of the Lodispoto, Holcombe, Jr., or Robinson designs is able to be worn throughout the activities of a normal day with the extraordinary amount of comfort and lack of fatigue as is available through the present invention and still accomplish all the exercise purposes of the present invention.
The Lodispoto design comprises a solid wooden sole attached to a single band sandal-type shoe upper. As well as being inflexible, the lower surface of the wooden sole of this device is shaped with a long incline curving upward from a forward standing contact point with a floor surface just rearward of the ball of a wearer's foot, to the forward most point on the sole. Such a forward incline by itself would cause a significantly greater amount of angular rotation of the plane of a wearer's foot about the axis of the wearer's ankle when walking, than that which is required in use of the instant invention. Yet, an even greater amount of such rotation is required via the sandal-type strap arrangement of the Lodispoto design, producing a flip-flop type movement between the rear portion of the device and a wearer's heel when walking. Although sandal-type arrangements may be used as part of the present invention, the significantly flat nature of a lower surface of the instant invention allows for wearer's thereof to accomplish the purposes of the invention with significantly less angular rotation and attendant exhaustion than that which is required in using the Lodispoto device.
The Holcombe, Jr., device includes the same forward inclining plane problem as the Lodispoto device, although to a lesser extent, due to the use of a shorter forward plane, a complete shoe upper and more flexible sole materials. The Holcombe, Jr., design is further severely limited in its application, since it is made as a purely exercise device without the intended purpose of being worn in more fashionable settings as a wearer of the device may wish to attend throughout the course of a normal day, were such continued wear feasible. The design of Holcombe, Jr., is an attempt to overcome the fashion difficulties associated with both the Lodispoto and the Robinson designs, by providing a forwardly inclining plane immediately below the sole of a wearer's foot inside footwear of the device. Although the Holcombe, Jr., design is more fashionable than the other cited prior art, it is still severely limited in its ability to provide the great amount of fashion variety which is available with exercising footwear using the instant invention. The Holcombe, Jr., is further severely limited in its ability to provide a substantially hidden inclined plane of such an angle between upper and lower surfaces of the inclined plane as that which is available with the instant invention.
Although these and other such devices now in the prior art have attempted to address similar exercise needs as that addressed by the instant invention, they have failed to address both the need for such devices to be worn for extremely long periods of time throughout the course of a wearer's day, and the need for such devices to accommodate an extremely wide variety of fashion, such that a wearer does not hesitate to wear the exercising device throughout all the activities of the wearer's day. As well, such devices have failed to achieve the replaceable-cost efficiencies available to users of the present invention.